I'm thinking of revalving my susp also and go to softer springs. My biggest concerns are the cam chain. With 17.5K miles have you already changed yours? With how many miles, if so?
Luckily here in Brazil we can found a lot of 610s from 2007 to 2009 with less then 3k miles, so I'll have an option to replace mine when needed.

Huh? You're replacing it with a used chain or replacing the motor?

A new chain is a $100 part. And my first went out @ about 10k the second has lasted longer, I don't actually know but i'd guess it's 17 or 20 and it's done.